This invention relates to magnetic suspension vehicles, and particularly to magnetic suspension vehicles with magnets that cooperate with stationary rail arrangements.
A magnetic suspension vehicle may be supported and driven in free suspension by magnetic attraction forces. It is known that there must exist, between the vehicle's magnets and an associated stationary rail arrangement, a suspension freedom and a clearance whose value is extremely small, such as from ten to fifteen millimeters. This is especially true in view of the electrical energy needed to support and drive such a vehicle.
The maintenance of the suspension freedom within any prescribed travel comfort criteria has two aspects. Partly it is a regulation-technique problem, which to this time could at least in principal be considered as solved. Secondly, it is a structural problem which at least partly concerns the structure and arrangement of the magnets. In this regard, practical solutions have been proposed for vibrationally decoupling the magnetic suspension vehicle from its magnets by elastically arranging the latter. For example, such decoupling was to be done by means of so-called (active or also passive) secondary spring devices between a magnetic frame and an overlying vehicle body. In this connection, in accordance with a further important contribution, the travel of a magnetic suspension vehicle about a curve could be improved by a proposed arrangement in which the magnets are members of a so-called magnet chain. The magnet chain is composed of several individual magnets arranged serially in the vehicle's longitudinal direction. The individual magnets are connected with the magnetic suspension vehicle by spring means operating parallel to their respective magnetic forces. This arrangement naturally makes it easier to maintain a prescribed suspension freedom and a correspondingly desired clearance between the magnets with the rail arrangement. This is so because of the relatively large number of individually flexibly movable magnets of relatively short length when compared to the longitudinal magnets hitherto used in known magnetic suspension vehicles.
In addition to this, the nominal flux strength of the individual magnets necessarily become smaller. Also, with equal power rise rate, the regulating range of the current or flux strengths, i.e., the so-called magnetic force magnification is also reduced. As a result, more suitable magnets can be constructed for a particular power or capacity and weight. In all cases, with the proposed arrangements, calculations must be made for irregular clearance differences relative to the rail arrangement along the magnetic chain at the interfaces between the adjacent individual magnets. Such distance differences can, under certain circumstances, lead to undesired feedback on the dynamic behavior of the magnetic suspension vehicle, and therefore, result in impairment of travel comfort.
An object of the invention is to improve magnetic suspension vehicles.
Another object of the invention is to avoid the aforementioned shortcomings.